Methods and devices for optical monitoring and rapid analysis of drying droplets

ABSTRACT

Abstract of the Disclosure 
     Devices for optical monitoring and rapid analysis of a drying droplet are presented and include a droplet deposition means, an optical recording means, and a computer control and image analysis means. In several preferred embodiments, a pipette is used to deposit one or more droplets in parallel onto a slide, a plate or a film, and a digital microscope is positioned either above or below the droplet to record a timed sequence of images of the process of drying thereof. Various chemical compounds coating the deposition slide can be used to enhance the test further. Image analysis includes data filtering, dividing the image into a plurality of overlapping windows, and analysis of formation and change in patterns over time. If used with biological fluids, the devices and methods of the invention can be used for rapid diagnosis of a variety of conditions and diseases.

Detailed Description of the Invention BACKGROUND OF THE INVENTION

The present invention relates generally to methods and devices for rapid analysis and determination of composition of multi-component solutions by means of optical monitoring and evaluating the patterns formed during the process of drying of at least one droplet of such solution. More particularly, the invention relates to specific pattern recognition methods for rapid diagnosis of the state of a biological fluid.

For the purposes of this description, the word “solution” is used to describe a liquid, which is a product of an act or process by which a solute (whether solid, liquid, or gaseous) is absorbed into and dissolved by a solvent liquid. The solute can be generally regained from the solution by evaporation or drying of a solvent. Suspensions and emulsions are also included in the general category of solutions.

A sub-set of solutions, which is of particular interest for the purposes of the invention, is a category encompassing biological fluids. The term “biological fluid” includes but not limited to the following examples of bodily fluids from animals or humans: blood and blood products such as serum or plasma, saliva, urine, nipple aspirants, synovial fluids, cerebrospinal fluids, sweat, fecal matter, bile, tears, bronchial lavage, swabbings, needle aspirants, semen, vaginal fluids, pre-ejaculate, etc.

The methods of analysis of a solution using the pattern formed by a dried droplet has been known in the prior art for a long time. Initial observations on the potential diagnostic information contained in the patterns formed by dried biological fluids were made over 30 years ago. At the end of the 1960’s, the relationship between hormonal changes during the female menstrual cycle and the crystallization of saliva was discovered. Formation of a unique pattern called ferning by a dried droplet of saliva correlates with the fertile period and is related to ovarian function and endocrine activity. Later studies have shown that salivary progesterone concentrations in samples collected by women daily, over extended periods of time, can serve as a reliable means of assessing ovarian function. Based on clinical evidence on the efficacy of detecting a woman’s fertile periods by observing characteristic ferning patterns in dried saliva, several US patents were issued on simple optical devices for determining fertile periods. The US Patents No. 4,815,835 by Corona and 5,572,370 by Cho are typical examples of such devices. OvuLook, LLC, a division of TCI Optics, Inc., has developed a commercial device called OvuLook™ and in December of 2001 received FDA clearance for an estrogen based saliva tester that reads ferning patterns.

One of the first attempts to use information contained in the patterns formed by dried biological fluids is presented in the US patent No 4,847,206 issued in 1989 and entitled “Method for the crystal morphological analysis of blood and urine, for early diagnosis and for the production of medicaments”. Examples of dried blood patterns corresponding to certain diseases are described, according to experimental data presented in that patent. The samples used for obtaining the patterns shown in that US Patent require a complex and long preparation procedure, which includes many steps such as diluting blood or urine by water, distilling it, calcining the dry cake by heating at a constant rate for a period of 60 to 70 minutes to a temperature of about 600 ^(o)C, cooling the calcinate for about 2 to 4 hours to a temperature of about 150 ^(o)C, and several other steps, which altogether make the proposed method hardly practical.

During the last decade, several publications correlated patterns formed by dried droplets of biological fluids with pathological or physiological processes in the organism. E. Rapis, who extensively studied the self organization of proteins in dried drops, recently reported on significant structural differences in the patterns of dried blood plasma films for healthy and cancer patients. In particular, in the article entitled “A change in the physical state of a nonequilibrium blood plasma protein film in patients with carcinoma” published in Technical Physics, Vol. 47, No. 4, 2002, pp. 510-512 and incorporated herein in its entirety by reference, the morphologies of changes of blood plasma in phase transitions are described. It is shown that patients with various types of cancers have a profoundly different characteristics of protein film self-assembly as opposed to healthy patients. This suggests that observing biological liquids may allow for rapid cancer diagnosis. Other papers of interest, which are also incorporated herein by reference include an article entitled “Magnetic sensitivity of protein” published in Tech Phys Lett 23(4), 1997, pp. 263-267 and an article entitled “properties and symmetry of the solid cluster phase of protein” published in Technical Physics Vol. 46, No. 10, 2001, pp. 1307-1313.

Yakhno et al. conducted extensive studies of various medical and non-medical applications of the drying droplet approach. Results of their studies are summarized in the PCT application No. WO 02/059595 incorporated herein by reference in its entirety and other publications. The major focus on their studies was not the analysis of formed patterns but measurements of “acousto-mechanical impedance” (AMI) of the oscillating quartz on which the droplet of a tested liquid was drying. Several applications of the method were explored, such as quality control of beverages and liquid foods, detection of odors by measuring solutions through which “scented” air was bubbled, and medical diagnostics based on measurements of temporal changes of AMI in the course of drying of a droplet of biological fluids: blood plasma, urine and saliva.

Yakhno reported various potential diagnostic applications of acoustical monitoring of the droplet drying process. It was demonstrated that the drying dynamics of a droplet of blood plasma from a pregnant woman with normal pregnancy differs significantly from that of women at risk for spontaneous abortion. It was also shown that the dynamics of blood serum droplet drying is different for patients with breast cancer and healthy women. The patterns for cancer patients have distinct characteristic features different from those for healthy women, such as larger structural elements and well-defined linear formations. Difference in the patterns for two types of cancer is also quite obvious. Pregnancy results in characteristic patterns. Moreover, there is a clear difference in the patterns for the in-time versus pre-term delivery.

Another example of using the patterns formed by the dried biological fluid droplet is described in the Russian Patents No. 2,127,430 by Buzoverja et al and 2,007,716 by Shabalin et al. The sample of fluid is dried and then the so-called “crystallogram” or pattern is analyzed for the presence of pathological markers.

A general process of determining the biological state through discovery and analysis of hidden biological data is described in the US Patent Application No. 2003/0004402 by Hitt et al. incorporated herein by reference in its entirety. The methods described in this patent application concern processing large volumes of data related to a biological fluid. This patent indirectly provides some useful background information for some aspects of the method of the present invention. More specifically, the use of databases for comparison with the patient’s sample as well as neural network based learning systems are described in the patent and may be used for some aspects of the method of the present invention.

This and other methods have a disadvantage of having only the final pattern of the dried droplet available for analysis. There is no mentioning in the prior art of analyzing the dynamics of structural changes in the sequence of patterns formed by the sediment in the drying droplet although the multitude and sequence of patterns formed and the time intervals between formation of certain patterns give a substantial information about the state of the solution.

The need therefore exists for such methods and devices that allow the optical monitoring and analysis of the state of a solution based on the dynamics of drying of a droplet of such solution.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to overcome these and other drawbacks of the prior art by providing novel method and devices for optical monitoring of a drying droplet to provide a rapid analysis of a solution.

It is another object of the present invention to provide diagnostic methods and devices for determining a biological state based on analyzing the dynamics of pattern formation of a biological fluid.

It is a further object of the present invention to provide enhancement for diagnostic methods and devices by using slides with different target agent coatings specifically interacting with the components of the droplet of a solution and optically monitoring the pattern formation sequence while drying that droplet thereafter.

It is yet a further object of the present invention to provide methods and devices for detecting changes in pattern sequence of a droplet of a biological fluid indicating the presence of a disease state (such as cancer for example) as well as monitoring the progress of treatment thereof.

It is yet a further object of the present invention to provide methods and devices for detecting such disease as well as monitoring the progress of treatment thereof at a location other than a medical office such as at the patient’s home, work, recreation, or another remote place.

It is yet another object of the invention to provide methods and devices for detecting specific agents by analyzing differences in the pattern formation dynamics at different rates of drying of a droplet of a solution including a biological fluid.

The present invention encompasses methods of determination of a multi-component fluid composition by analyzing the sequence of patterns formed during drying of a droplet of said fluid. More specifically, the present invention encompasses methods of assessing biological fluids and diagnosing diseases by recording the dynamics of said pattern formation and relating said dynamics to the global database on corresponding biological fluid pattern dynamics. The invention further encompasses methods of detecting chemical and biological agents by analyzing the sequence of patterns formed by drying droplets of solutions of substances selectively interacting with the surface of the slide coated by various target agent coatings. The invention also encompasses methods of detecting changes in the dynamics of drying droplets of biological fluids for the diagnosis of diseases, such as cancer and pathogen infections. The invention further encompasses methods of analyzing specific changes in the dynamics of drying droplets of biological fluids for the monitoring of treatment of diseases. The present invention also encompasses methods of detecting specific agents by analyzing differences in the pattern dynamics at different rates of droplet drying. The invention further encompasses methods of detecting changes in the dynamics of drying droplets of fluids in industrial processes such as food and drug manufacturing such as for the purposes of controlling or monitoring the purity, quality, or other desirable characteristics of the fluid.

The invention also encompasses devices for recording and analyzing said dynamics of the drying droplet pattern. In its most basic form such device includes a droplet deposition means, an optical recording means for obtaining a sequence of patterns formed by at least one drying droplet and transforming them into a form suitable for further analysis, and a computer control and analysis system to analyze the images and provide the output result.

In practical terms, the device of the present invention in its most basic form includes a simple deposition plate such as a glass or quartz plate or slide serving as a droplet deposition means. Calibrated droplet deposition devices well known in general in the prior art can also be used effectively as more sophisticated droplet deposition means as will be described in more detail below. Advantageously, deposition plates with various coatings containing target agents can be used to enhance the sensitivity of the analysis of the present invention.

A simple video camera mounted to record the formation of drying patterns would serve as an example of the most basic optical recording means for the system of the present invention. Better yet, a CCD camera connected to a computer would provide the data stream input needed for further analysis of the solution. Other more sophisticated optical recording means and droplet deposition means are described in greater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the subject matter of the present invention and the various advantages thereof can be realized by reference to the following detailed description in which reference is made to the accompanying drawings in which:

FIGURE 1 is a block-diagram of the first embodiment of the invention showing optical recording means located underneath the droplet deposition means,

FIGURE 2 is a block-diagram of the second embodiment of the invention showing the optical recording means located above the droplet deposition means,

FIGURE 3 is a schematic drawing of the third embodiment of the invention showing film means for droplet deposition with one or more droplets in parallel being analyzed by the optical recording means,

FIGURE 4 is a schematic drawing of the fourth embodiment of the invention showing multi-lane film, each lane is coated by a different target agent for enhancing the test sensitivity,

FIGURE 5 is a schematic drawing of the fifth embodiment of the invention showing a multi-tip pipette for simultaneous processing of multiple samples at the same time,

FIGURE 6 is a block-diagram of the sixth embodiment of the invention showing two-channel pipette means,

FIGURE 7 is a block-diagram of the seventh embodiment of the invention showing inverted droplet deposition means to allow for droplet drying in inverted position,

FIGURE 8 is an example of pattern sequence recorded with the device of the present invention,

FIGURE 9 illustrates the results of analysis of the patterns shown on Fig. 8,

FIGURE 10 illustrates a general view of the home based version of the diagnostic devices according to the present invention,

FIGURE 11 shows a schematic block-diagram of the device shown on Fig. 10, and

FIGURE 12 shows an electrical diagram of the device shown on Fig. 10 and its interaction with a remote hospital image analysis device.

DETAILED DESCRIPTION OF THE FIRST PREFERRED EMBODIMENT OF THE INVENTION

A detailed description of the present invention follows with reference to accompanying drawings in which like elements are indicated by like reference letters and numerals.

The first embodiment is shown schematically on Fig. 1 and includes a droplet deposition means 10 with an optical recording means 60 and a computer control and image analysis means (not shown). The droplet deposition means 10 in turn comprises a pipette 30 adapted to deposit predefined volumes of solution as a droplet 100 onto a deposition plate means 50 supplied by a slide feed 16. Examples of a deposition plate include glass or quartz plate, slide, or cassette supplied from the glass cassette compartment 20 supported optionally by a glass separator 25 or from another appropriate source. The device of the invention includes further provisions to position the droplet on a deposition plate means 50 onto a sample holder 45 inside an optional climate controlled chamber 40 and illuminate it by a light source 35.

In a preferred embodiment, the light source 35 provides diffused polychrome light, which permits achieving best discrimination between colored structures of the droplet. Preferably, blue, green, and red LED diodes with three channels of electrical current control are used as a light source 35.

Optical recording means include in this case a digital microscope 60. Alternatively, a CCD camera can also be used such as for example a Pixera 120es Pro color scientific grade CCD camera attached to a long focal distance zoom lens such as Navitar. In this embodiment, the optical recording means are mounted underneath the droplet and observe the drying sequence from the bottom through a clear deposition plate.

The computer control and image analysis means generally consists of a data collecting means connected to the optical recording means such as a digital microscope and adapted to receive the stream of data containing the timed sequence of images of the drying droplet. Once collected, the images are then analyzed to look for specific patterns and specific timed of formation thereof and the results are then provided. The details of the image processing and analysis are described below in greater detail. One important aspect of the computer control and image analysis means though is the ability to recognize the end of the drying cycle so the system is capable of advancing the droplet deposition means to the new one and discard the old one automatically. Alternatively, the duration of the drying cycle is set for a predetermined time.

After completion of the data collection, the droplet and the deposition plate are discarded into a glass collector 55.

DETAILED DESCRIPTION OF THE SECOND PREFERRED EMBODIMENT OF THE INVENTION

The block-diagram of the second embodiment of the present invention is shown on Fig. 2 including all the same elements as the first embodiment but in a different orientation. In particular, the optical recording means 60 is located above the climate control chamber 40 and observes the drying droplet from the top. The droplet in that case may be deposited on any suitable deposition plate, which does not have to be optically transparent.

Observing the droplet from the top or the bottom or optionally from both sides simultaneously (not shown on the drawings) reveals various details of the dynamics of the drying process.

DETAILED DESCRIPTION OF THE THIRD PREFERRED EMBODIMENT OF THE INVENTION

The schematic depiction of the third embodiment of the present invention is shown on Fig. 3 including an optional solution feed device 15 to supply the pipette means 30 and a different droplet deposition plate means, namely a film 51, which accepts one or more deposited droplets in parallel. The film is advanced from one roller over to another via a film advancing means 52 such as a stepper motor for example. The motor is controlled so that the advancement of the film is started and stopped in such a way that the droplet is positioned under the optical recording means 60 for a sufficient time for drying to occur and data collection to proceed without moving the droplet. Once the data is collected, the film is advanced to that a fresh sample is positioned in the field of view of the optical recording means. Used droplets are discarded with the used roll of film.

Optional provisions are contemplated for adjustment means to position the optical recording means 60 at various points across the width of the film so as to allow more samples to be processed per unit of length of the film.

Additionally, the optical recording means may have optional provisions to record the drying sequence and pattern forming of more than one droplet at a time. Further data processing step should in this case be capable of recognizing that fact and separate data from more than one droplet.

DETAILED DESCRIPTION OF THE FOURTH PREFERRED EMBODIMENT OF THE INVENTION

The fourth embodiment of the present invention includes provisions to record the drying of a droplet deposited onto deposition plate or film coated with a compound selectively interacting with certain components of the tested solution. Such compound may be of different nature but the general purpose of such coating is to increase the sensitivity of the test by modifying the drying process dynamics following specific interaction between components of the solution of interest and the coating compound.

In a further advancement of this concept, Fig. 4 shows the deposition film coated with more than one compounds and forming deposition lanes on the film 51a. It is envisioned that the pipette means 30 may be capable of depositing one droplet at a time or more than one including depositing droplets in parallel to all lanes on the deposition film or plate. Optical recording means 60 are also capable of recording the drying patterns of one or more droplets in parallel therefore the speed and statistical significance of testing is increased further while its sensitivity is enhanced by the target agents.

Various coating compounds may be used for the purposes of the invention. The methods of the invention include detecting a specific solute in the tested liquid droplet by drying it on a surface coated by a compound, which interact specifically by macromolecule-to-macromolecule action. These macromolecules may be any combination of protein (including antibody), nucleic acid, carbohydrate, or synthetic polymer; macromolecule-to-small molecule interactions; or small molecule-to-small molecule interactions; or interactions that are non-specific via charge-to-charge; or hydrophobic interactions; or other nonspecific surface effects.

The present invention also encompasses methods of detecting specific compounds by analyzing differences in the pattern dynamics of droplet drying as a function of the following preferred groups of specific compounds :

-   salts such as for example ammonium sulfate; -   detergents and surfactants for example dodecyl sulfate or lauryl     sulfate and various cationic detergents such as cetyl (or     hexadecyl)-trimethyl ammonium bromide, dimethyldioctadecylammonium     bromide, dioleyldimethylammonium chloride, and     1,2-dioleyl-3-N,N,N-trimethylaminopropane chloride; -   cosolvents especially those that are miscible with water, such as     ethanol, isopropanol, and dimethyl sulfoxide; -   charged or neutral polymers such as for example polyethylene glycol     or polypropylene glycol; -   specific agents in a liquid containing an optical marker that     interacts or binds specifically to the target agent; and -   denaturants.

DETAILED DESCRIPTION OF THE FIFTH PREFERRED EMBODIMENT OF THE INVENTION

Fig. 5 shows yet another preferred embodiment of the present invention in which a pipette 30a is equipped with a multi-tip to allow multi-channel deposition of the solution onto a film or a deposition plate.

This embodiment allows further increase in productivity of testing of a large number of samples.

DETAILED DESCRIPTION OF THE SIXTH PREFERRED EMBODIMENT OF THE INVENTION

Fig. 6 shows yet a further embodiment of the present invention including a pipette 30b having multi-channel capability in the direction of film advancement. The drawing shows a two-channel pipette capable of depositing two droplets one close to another so that further processing and data collection can be done with two samples at a time rather than just one.

Of course, those skilled in the art would readily understand that two types of pipettes described for the fifth and sixth embodiments may be combined in such a way that more than one droplets is deposited in both directions – along and across the deposition plate or film.

DETAILED DESCRIPTION OF THE SEVENTH PREFERRED EMBODIMENT OF THE INVENTION

Finally, Fig. 7 shows another preferred embodiment of the invention in which the droplet deposition plate is inverted upside down so that the optical recording means are allowed to record the drying of the droplet in this inverted orientation. The deposition film 51 is rolled off the first roller 53 and the droplet of a solution is deposited thereon from a pipette 30. The film is then inverted about the roller 56 and the optical recording means 60 are mounted below and used to view, record and transmit data about the sample drying in this position.

IMAGE ANALYSIS

Once the optical data is collected, it is then processed to obtain the test results using two main steps – data filtering and data analysis.

Data filtering can be done with known image processing software packages and may include one or more of the following digital transformations:

-   reversed tone curve to convert all digital images to linear     intensity scale; -   background subtraction to avoid CCD/CMOS-related artifacts and     optical system flaws; -   noise reduction and passing the image through a low-pass     (low-frequency) filter; -   grayscale conversion of images taken both regularly and with a     polarized light; and -   thresholding to enhance the desirable features of the image,     optionally applied several times.

Analysis of changes over time within a relatively small window (portion of the image) is the key element used for the image analysis according to the methods of the present invention. The analysis of a set of overlapping windows that cover the entire image provides broad quantitative and qualitative information about changes in the image as a function of position and time.

The selection of the size and arrangement of the sample windows over the investigated image is important. The selection of the window arrangement could depend on image features and convenience for visual analysis. Those two requirements do not always correspond. For example, it is known that the footprint of a drop of dried liquid is generally a circle, which suggests a radial window distribution; however, a radial distribution of circular windows would result in too dense positioning of the windows close to the center of the drop. Therefore, triangular or square meshes of the windows would be used, with the density of the mesh depending on window shape. Meshes are used for automatic analysis. They are generated automatically on the basis of a small set of density parameters.

For illustration purposes, sequence of windows along single segments has been used. The window sequence geometry includes linear segments, where the analyzed windows are arranged on a line, for example, along a radius of the drop footprint; and arc segments, where the windows are positioned at a certain distance relative to the center of the drop. The first stage of the analysis will employ single segment window arrangements with mostly manual interactive positioning of the segments.

Multiscale Approach and Different Place-Different Density Approach:

The patterns of changes in the images can be viewed at any level of sampling (discretization). It is possible that different parts of the image go through different patterns of changes. Therefore, the method for detection of initiation of essential changes and subsequent tracking must be adaptive to the situation. The search for the beginning of an essential change must be conducted at different levels of image sampling. Only stable and reproducible changes must be tracked. For example, for the footprint of a drying drop similar conditions will be found at approximately radial rings around the drop’s center. The time scale also should be multiscaled, as changes are relatively quick, and there is no point in tracking every frame (image) given the time and resource intensive calculations. Assuming that propagation of the observed changes is relatively continuous, the detection of a change at any level of sampling will motivate more refined search on other levels and under more narrow time scales.

Analyzed Parameters:

The selection of the set of analyzed parameters is based on commonly accepted advanced image recognition techniques and include:

-   Visualization of image data with scattergrams, histograms, line     profiles and time-space plots; -   Building time-dependent functions of image intensity such as     average, mean standard deviation, max/min intensity ratio, and their     derivatives and combinations for the same sample window and for the     different sample windows; -   Building shape and texture related functions of the image such as     roughness, calculated fractal dimension of the image, border-related     integrals of the image, mean direction angle, and their derivatives     and combinations for the same sample window and for the different     sample windows.

Data Processing:

The source of information is a sequence of images of a droplet pattern recorded as separate images or as an integrated data file in AVI or MPEG format. The image resolution normally is 600x800 pixels with 24bit color, but the resolution could be higher and a gray color palette also could be used. The actual format of the data, as well as the image color and resolution, depends on the camera and digital media used. The number of images may be several hundred or even several thousand. The software will preferably execute a multi-scale pass through the image sequence starting with a large step. For example, analyzing every 100^(th) image and discarding ranges with small variations is a reasonable way to go. The ranges with essential variations are then passed through again with smaller step. The procedure is repeated until the kernel of the change is localized with the desired accuracy.

The image processing may be done after all data is collected. However, in a preferred embodiment, the data is analyzed, as it becomes available so that only useful information is recorded while other data is discarded. Another advantage of “live” analysis is the ability to detect the end of the drying cycle and advance the system to the next droplet to be analyzed without waiting for the expiration of a preset time delay.

The value of a parameter and its averaged temporal derivative is recorded and analyzed. Not every parameter change in a window is noted as valuable. A similar manner of change is assumed for equally placed windows (along the radius of the droplet). Therefore, a continuous change for circular (or close to circular) zones is marked in favor of the analyzed parameter. Isolated changes of a parameter are marked as a negative property of the parameter. The evaluation of the parameter is based on how many positive and negative marks the parameter is assigned. The parameter changes is then visualized and examined manually, in order to test the proposed algorithm for parameter analysis.

After such examination, the final set of the parameters is selected. The location of primary changes, sampling and filtering schemes for those parameters are also recorded.

To improve the stability of the result, the same experiment may be repeated several times and overlapping sets of the examined parameter are selected.

Various means are contemplated to enhance the sensitivity of the methods of the present invention in addition to the described above concept of coating the deposition means with a target agent compound to cause a reaction with a portion or the entire chemical structure of the droplet. One method of enhancement is generally referred to as “zooming”. The essence of it is to adjust the speed of dehydration or drying of the droplet by various available means such as humidity, temperature, mechanical agitation, electrical, magnetic, sound, or light stimuli, etc. when the concentration of certain critical components has reached a certain critical predetermined level. It is advantageous to slow down or even completely stop the drying process by adding solvent to the droplet once the process of crystallization or another sharp structural transition has started or about to start so that more information can be extracted by the device of the invention from the process of drying of the droplet. The climate control system can be used for the purposes of zooming. More than one zooming can be used for analysis of a droplet having a complicated structure.

Another method to further extend the sensitivity of the method and the device of the present invention is to use so-called “pattering” for the purposes of the deposition surface of the deposition means of the invention. Specifically, the surface of a deposition means may contain a series of geometrical shapes such as squares, lines or other patterns rather than being simply flat to change advantageously the process of drying of the droplet. Patterning with biological ligants or nucleation centers can be used in addition or in place of geometrical patterning of the surface of the deposition means. Such patterning can further increase the sensitivity by influencing the process of crystallization especially if it is optionally combined with application of a target agent compound to the surface of the deposition means to induce different crystallization kinetics or geometry.

Yet another method to further extend the sensitivity of the method of the present invention is to use various types of illumination of the drying droplet so that the device of the invention can better detect some particular aspects of crystallization. Specifically, visible, polarized, IR, fluorescent, or UV light can be used separately or in combination for illumination of the droplet as well as a light of a certain predetermined wavelength or a range of wavelengths.

Of course, all of the above methods of enhancing the sensitivity of the analysis may be deployed separately or in combination with other methods.

An example of operation is illustrated on Fig. 8 showing several selected images of a blood serum droplet while drying. The numbers given below each image represent the time from the start in seconds. Fig. 9 shows results of analysis of the pattern formed by the drying droplet. The lines represent the changes in time of some of the parameters of the pattern within the selected part of the image (black square).

The actual diagnosis of the patient may be performed using the databases of the known images from both healthy individuals as well as patients with known diseases using well known in the prior art techniques such as those described by Hitt for example as discussed earlier.

HOME-USE APPLICATIONS

Figures 10 through 12 show the home-based version of the device designed for diagnostic purposes as well as remote monitoring of a patient in home settings. The general view of the device is shown on Fig. 10 and includes a pipette 130 along with a fluid collection container 131. The actual device consists of a housing 101 with an optional cover 102, which reveals a disposable droplet deposition slide 150 when open. The slide 150 is supplied from a side cartridge unit 120.

Further details of the device are revealed on Fig. 11 and include a optical recording and computer processor unit 160; climate control unit 140 allowing adjustments to the temperature and humidity of the droplet environment through a fan (not shown) drawing conditioned air from the chamber of the unit 140 and over the slide 150; automatic slide movement means 116 to draw the slide 150 into and out of the business end of the device; and the lighting means 135 to illuminate the droplet during its drying and image recording by the optical means 160. After the sequence of images of the process of drying is recorded, the slide 150 is automatically discarded into the bin 155. Conveniently, the unit 120 can be combined with the unit 155 to form a single use cartridge allowing several slides to be used and then discarded back therein so the user has to simply replace the entire assembly of both units once in a while.

The electrical diagram of the device and the details of its interaction via a wire or wireless connection with a remote data processing and analysis center such as at a hospital is shown on Fig. 12. Importantly, the procedure of use of the device is very simple and includes collecting of a sample of biological fluid by the patient into a fluid container 131 (such as saliva or urine for example); measuring the volume with pipette 130 and depositing the correct amount onto a slide 150. After that the rest of the process is fully automated and includes drawing of the slide 150 inside the device and activating of the process of drying the droplet and recording the sequence of images according to the methods described in more detail above. The information is then processed by the unit 160 and communicated to a remote location such as at the hospital via a built-in remote communication means.

One of the key features of the home-based version of the present invention is adaptive data processing, which enables the detection system to “learn” peculiarities of collected data sets for a particular person. Learning algorithms make it possible to significantly increase the sensitivity of present invention by fine tuning the device to specific features of a given subject. The learning ability of a home-use medical diagnostic system, such as home-use of the present invention, is based on the fact that the data collected during extended period of time provides means for defining much more precisely the “normal state” of an individual and thus, detecting meaningful deviations from the normal state with greater sensitivity.

Medical logic for diagnosis is typically based on the principle that healthy state of body is an objective notion and should be defined by "normal" range for certain parameters that are the same for a given population group. At the same time, it is well known that a notion of “normal” obtained on statistical basis can significantly differ from a “normal” value for a particular patient. For example, the pulse rate of 100 beats per minute could be normal for one person and extremely dangerous for another. Even for the same person, the measures normal in one condition can be hazardous in a different body state. In the home-use system a different principle can be implemented in which the ranges of parameters that define the healthy state are determined individually after collecting a sufficient body of data over an extended period of time.

Although the invention herein has been described with respect to particular embodiments, it is understood that these embodiments are merely illustrative of the principles and applications of the present invention. For example, if the devices and methods of the invention are used with biological fluids, a variety of medical conditions and diseases may be rapidly identified. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. 

1. A device for optical monitoring and rapid analysis of a drying droplet, said device comprising: a droplet deposition means adapted to accept said droplet, an optical recording means positioned about said droplet deposition means and adapted to record a timed sequence of images of said droplet during a process of drying thereof, and a computer control and image analysis means including data collecting means operably connected to said optical recording means to collect said timed sequence of images of said drying droplet, said computer means also including image analysis and processing means to provide rapid analysis of said droplet.
 2. The device as in claim 1, wherein said droplet deposition means further comprising: a droplet deposition plate means, and a pipette means adapted to deposit said droplet of said solution onto said droplet deposition plate means, said pipette means positioned above said droplet deposition plate means and in operable relation therewith.
 3. The device as in claim 1, wherein said droplet deposition means comprising said droplet deposition plate means including a slide supplied by a slide feed from a glass cassette compartment.
 4. The device as in claim 1, wherein said droplet deposition means comprising said droplet deposition plate means including a film supported by a first roller and a second roller, said droplet deposition means further including control means to advance said film from said first roller to said second roller.
 5. The device as in claim 4, wherein said film is divided into a plurality of parallel lanes, said droplet deposition means further including a pipette having multiple tips adapted to deposit a plurality of droplets one on each lane of said film in parallel.
 6. The device as in claim 5, wherein said lanes each coated with a target agent compound to enhance the sensitivity of said analysis.
 7. The device as in claim 6, wherein said target agent compound is selected from a group consisting of a salt, a detergent, a surfactant, a cosolvent, a polymer, an agent containing an optical marker, and a denaturant.
 8. The device as in claim 4, wherein said droplet deposition plate means further comprising a third roller, said film adapted to be turned around about said second roller to invert thereof and then directed towards said third roller.
 9. The device as in claim 1, wherein said optical recording means positioned underneath said droplet deposition means to observe said droplet from below.
 10. The device as in claim 1, wherein said optical recording means positioned above said droplet deposition means to observe said droplet from above.
 11. The device as in claim 1, wherein said computer control and image analysis means further comprising remote communication means.
 12. The device as in claim 1, wherein said droplet is a biological fluid.
 13. The device as in claim 1, wherein said optical recording means including a digital microscope and a light source positioned on the opposite side of said droplet deposition means from said digital microscope.
 14. The device as in claim 1, wherein said droplet deposition means including a climate control chamber.
 15. A method for optical monitoring and rapid analysis of a drying droplet comprising the steps of: providing a droplet deposition means, depositing a droplet onto said droplet deposition means, providing an optical recording means, recording a timed sequence of images of said droplet during a process of drying thereof, and analyzing said timed sequence of images to provide rapid analysis of said droplet.
 16. The method as in claim 15, wherein said droplet is a biological fluid and said step “e” includes providing a diagnosis for a patient from which said biological fluid is taken.
 17. The method as in claim 15, wherein said step “b” including depositing a plurality of droplets at the same time.
 18. The method as in claim 15, wherein said step “e” including a step of data filtering.
 19. The method as in claim 15, wherein said step “e” further including a step of dividing each image of said sequence into a plurality of overlapping windows and analyzing each window for formation and change of patterns of said drying droplet over time.
 20. The method as in claim 19, wherein said step of dividing each image into a plurality of windows further including a step of measuring informativity of said window.
 21. The method as in claim 15, wherein said step “e” further including a step of conducting a multi-scale pass through said timed sequence of images starting with a large step and repeating thereof with smaller steps until a kernel of a change is localized.
 22. The method as in claim 15, wherein said step “a” of providing a droplet deposition means further including coating said means with a target agent compound to cause a chemical reaction with at least a portion of said droplet.
 23. The method as in claim 1, wherein said step “a” of providing a droplet deposition means further including patterning said droplet deposition means to influence the process of crystallization of said droplet onto said droplet deposition means.
 24. The method as in claim 23, wherein said patterning is a geometrical patterning.
 25. The method as in claim 23, wherein said patterning is with biological ligands or nucleation centers.
 26. The method as in claim 15, wherein said step “a” of providing a droplet deposition means further including providing a light means to illuminate the droplet, and said step “d” further including illuminating the droplet with visible, IR, UV, or fluorescent light of a predetermined wavelength.
 27. The method as in claim 15, wherein said step “d” further including at least one step of zooming to slow down the drying process when a sharp structural transition of the droplet is about to occur.
 28. The method as in claim 27, wherein said step of zooming is achieved by varying one or more of the parameters affecting the speed of drying of said droplet, these parameters selected from the group comprising temperature, humidity, mechanical agitation, electrical stimuli, magnetic stimuli, sound stimuli, and light stimuli.
 29. The method as in claim 28, wherein said droplet deposition means further including a climate controlled chamber surrounding said droplet and said step of zooming including varying a temperature or humidity inside said climate controlled chamber.
 30. The method as in claim 1, wherein said step “e” further including a step of determining an end of the drying process of said droplet.
 31. A home-based diagnostic device for optical monitoring of a drying droplet of a biological fluid from a patient, said device comprising: a droplet deposition means adapted to accept said droplet, an optical illumination and recording means positioned about said droplet deposition means and adapted to record a timed sequence of images of said droplet during a process of drying thereof, and a computer control and image analysis means including data collecting means operably connected to said optical recording means to collect said timed sequence of images of said drying droplet, said computer means also including remote communication means to transmit said data to a remote location for further data analysis to provide diagnosis of said patient.
 32. The device as in claim 31, wherein said droplet deposition means further including a droplet deposition plate and a slide movement means adapted to automatically draw the deposition plate into said device to start the drying process to collect said sequence of images and to discard said deposition plate once said drying process is complete. 